[OpenSIPS-Users] Adding a a=sendrecv line to SDP

[Bogdan-Andrei Iancu]

Hi Andreas,

AFAIK, this sendrecv is optional (it is assumed by default, if not 
present).

What you can try is something like:
     subst_body('/^m=(.*)/m=\1\r\na=sendrecv/g');

to add a"sendrecv" line after each `m` line (stream). Still, this may be 
pron to errors as you may already have some indication there (like a 
sendonly)

Best regards,

Bogdan-Andrei Iancu

OpenSIPS Founder and Developer
   https://www.opensips-solutions.com
OpenSIPS eBootcamp
   https://www.opensips.org/Training/Bootcamp

On 1/21/22 3:24 AM, Andreas Sikkema wrote:
> Hi,
>
> I am replacing an old hardware SBC with a simple OpenSIPS instance
> that basically does a little as possible. So topology hiding, rtpproxy
> between the "lan" and public side and a few choice header
> manipulations. The one problem I am having is that for some reason the
> platform on the "lan" side requires an "a=sendrecv" line in the SDP
> body.
>
> All the SDP body manipulations I have found are more of the replace
> this part of the body with that new value, while I just want to add a
> whole line to the end of the body. The old SBC would add this to each
> audio "stream" (not sure of the correct terminology here).
>
> I know this is not 100% kosher, because I can't force all the SDP
> bodies to be correct, but this is just a test platform that quickly
> needs a solution for the broken hardware. And I would really like to
> prevent spending money here. It's been a while since I looked into SDP
> manipulation using OpenSIPS.
>
> I am currently testing on an older OpenSIPS 2.x release, but could
> upgrade to something more recent when necessary.
>
> Anyone have an idea? Thanks!
>